Method for producing fuel distillates

ABSTRACT

The invention relates to the production of fuel distillates and may be utilized in the oil refining industry for the production of motor fuels and jet engine fuels.  
     The idea of the invention is that residual oil stock (fuel oil, tar oil, petroleum tailings) is mixed with a slate coal having the mineral part content of 45-60% by weight and the organic part content of 40-55% by weight and with the shale oil fraction, having the hydrogen content not less than 10.0% by weight, in the amount of 1.0-6.0% of the raw stock, then the resulting mixture is homogenized in a mixer at a temperature not lower than 80° C., and thermal conversion or hydrocracking is carried out. Fuel distillates (gasoline, diesel fuel, vacuum gas oil) are extracted from the products of thermal conversion or hydrocracking.

FIELD OF THE INVENTION

[0001] This invention relates to the field of oil refining industry and, more particularly, to methods for distillation of heavy still bottoms for producing fuel distillates by way of thermal conversion and hydrocracking with the use of donor-solvent processes.

PRIOR ART

[0002] In the conditions of the existing world trend to increasing the consumption of oil and oil products the oil refining industry is developed toward deeper oil refining. This task may be solved only by widely implementing new and economically advantageous technologies of deep refining of heavy hydrocarbon stock comprising asphaltenes and heavy metals (vanadium and nickel), such as fuel oil, tar oil, heavy oils (malthas), natural bitumens.

[0003] One of the most prospective and modern way for solving this task is combined cracking, by a thermal conversion or hydrocracking method, of a mixture of residual oil stock and coal, the latter being taken in the quantity of 5-30% of the weight of oil residue (RU,-A1No. 2009162, 1994; U.S., A1Ser. No. 4,544,479, 1985; RU, A1 No. 2076871, 1997).

[0004] In accordance with the known methods the said mixture is subjected to thermal conversion (viscosity breaking) for obtaining the products having lower viscosity and reduced amounts of heavy metals. Such stock and its distillates may be reprocessed into light fuel distillates by way of catalytic cracking.

[0005] This solution may not be considered as having no disadvantages. Thus, the relatively low degree of metal removal does not eliminate difficulties in the subsequent catalytic cracking of the product of that process; but even the use of modem catalysts, which are stable towards metals, requires their increased amounts, and this adversely affects the general economic parameters of this known solution.

[0006] Another well-known and applicable method for solving the said task is the process of hydrorefining of heavy oil stock with the additive grain size control (U.S., A1 Ser. No. 5,972,202, 1999).

[0007] The advantage of this process is its technological flexibility, i.e., by modifying the process parameters (temperature, pressure, volumetric rate, etc.) it is possible to achieve the maximum conversion and yield of the desired products.

[0008] The disadvantages of this process are the use of rather expensive catalytic systems, such as ferric sulfate, sulfides of other metals, ferric hydroxide, etc., which adversely affects the technical and economic parameters of the process.

[0009] Known in the art are methods for producing fuel distillates from residual oil stock, which include mixing residual oil stock with sapropelite and a liquid aromatic additive, carrying out thermal conversion or hydrocracking of the thus obtained mixture and finally separating the desired products (RU, A1 No. 2076891, 1997; RU, A1 No. 2057786, 1996).

[0010] In the known methods thermal conversion or hydrocracking is used for mixtures containing heavy oil stock (fuel oil, tar oil, mixtures of Western Siberian oils, heavy oils from the Buzatchi and Mangyshlak fields), sapropelite - Leningrad, Baltic, sulfur shale or Kuzbass sapromixite 1-10% by weight, crude shale oil or its fraction 220-340° C., 1-10% by weight, or tetralin or its alkyl derivatives at elevated temperature and pressure with subsequent separation of fuel distillates. The yield of fuel distillates is in the range of 55-60% by weight of the stock when using thermal conversion and up to 90% by weight of the stock when using hydrocracking. With the use of a hydrorefining process distillates produced by way of thermal conversion or hydrocracking may be reprocessed for producing light motor fuels, including motor gasoline and diesel fuel.

[0011] The disadvantage of the known methods is that they use the so-called “crude shale oil” as the aromatic additive, as well as tetralin or its alkyl derivatives.

[0012] This is conditioned by the fact that “crude shale oil”, as used in the known methods, is industrially produced by shale gasification. The quality of the crude shale oil thus obtained does not fully complies with the requirements to the liquid additive used as the activating agent for the processes of thermal conversion and hydrocracking of heavy oil stock, since that crude shale oil contains a great amount (up to 13% by volume) of oxygen-containing compounds (phenols) and up to 0.5% of mechanical impurities.

[0013] Tetralin is produced by way of hydrogenising technical products containing condensed aromatic hydrocarbons, mainly naphthalene and its alkyl derivatives. The process of producing tetralin and its alkyl derivatives is very expensive. Correspondingly, the final product is also relatively expensive.

[0014] The closest to this invention is a method of producing fuel distillates, which includes mixing residual oil stock with ground sapropelite and a liquid activating additive, homogenizing the obtained mixture and its thermal conversion or hydrocracking with subsequently separating the desired products (RU, A1 No. 2128207, 1999). In the known method a hydrogenated fraction with the boiling point in the range of 300 to 400° C. is used in the amount of 1-5% by weight as the liquid activating additive. The yield of fuel distillates is 55-60% by weight when using thermal conversion and up to 90% by weight when using hydrocracking. The known solution is disadvantageous in that the use of a hydrogenised fraction with the boiling point 300 to 400° C. as the aromatic additive also increase the cost of the final products due to the fact that for its production the additional stage of distillation separation and further hydrorefining are necessary in order to ensure higher hydrogen-donor properties for the fraction with the boiling point 300 to 400° C.

[0015] A rather high cost of the hydrogenised fraction with the boiling point 300 to 400° C. hampers the use of the known method in the oil refining industry.

DESCRIPTION OF THE INVENTION

[0016] The objective of this invention is to raise the efficiency of the method of refining heavy still bottoms, including reducing the cost of the final product.

[0017] The technical result of the invention is the elimination of using a hydrogenised fraction with the boiling point 300 to 400° C., while preserving the production capacity of the method.

[0018] The said technical result is achieved due to the fact that in the method for producing fuel distillates, which includes mixing residual oil stock with ground sapropelite and the liquid activating additive, homogenizing and carrying out thermal conversion or hydrocracking of the obtained mixture, and subsequently separating the desired products, the ground sapropelite before homogenization is activated mechanically in, at least, one disperser, as sapropelite a slate coal is used, which contains, in per cent by weight: 45-60% of the mineral part and 40-55% of the organic part, as the liquid activating additive the shale oil fraction is used with the boil-off limits 200 to 400° C. and containing hydrogen in the amount of at least 10.0% by weight, said slate coal and the shale oil fraction being taken in the quantities (% by weight of the stock) from 1 to 5 and from 1.0 to 6.0, respectively.

[0019] Furthermore, slate coals are used, which contain, in grams per ton: molybdenum 3-15, nickel 20-35, cobalt 3-10, chrome 30-40, copper 15-40 and lead 5-20.

[0020] Furthermore, slate coals are used, the mineral part of which contains, in per cent by weight: SiO₂  30-40 Cao  25-40 Na₂O 0.3-3.0 Fe₂O₃   5-10 MgO 1.5-5.0 P₂O₅ 0.1-0.7 Al₂O₃   8-15 SO₃ 1.5-5.0 TiO₂ 0.5-0.7 K₂O 2.0-5.0

[0021] Furthermore, homogenization is carried out in a mixer at the temperature from 80 to 100° C.

[0022] Furthermore, at the stage of mechanical activation slate coal is additionally ground down to the particle size of 30 to 100 microns.

[0023] The mechanical-chemical treatment is carried out in the known apparatus of Desi-14 type as well as in known dispersers (homogenizers) and homo-mixers.

[0024] Another additional embodiment is possible, according to which the mixture is double-homogenized.

[0025] According to the invention heavy oil stock (fuel oil, tar oil) is successively mixed with the liquid activating additive and sapropelite, where the sapropelite (slate coal) is preliminarily ground down to the particle size of 30 to 100 microns (preferably 50 to 100 microns).

[0026] The obtained mixture is mixed and intensively homogenized for the purpose of uniformly distribute the activating additives in the whole quantity of the raw stock.

[0027] In the process of grinding the solid activating additive and subsequently homogenizing the 3-component mixture the rather effective activation of the raw stock is achieved, where the additive sizes (0.3-0.5 nm) are commensurable with the sizes of molecules of the heavy oil stock (0.4-0.7 nm). This is of primary importance for creating the conditions for the optimal contacts between activating additives and the molecules of the raw stock.

[0028] The raw stock after such treatment may be subjected to thermal conversion or hydrocracking in less strict conditions in comparison to the known methods, namely: at the reactor temperatures from 415 to 440° C., the temperatures of the raw stock exiting the ftrnace from 450 to 490° C., the pressure from 4 to 10 MPa, the volumetric rate from 0.8/hour to 2.0/hour. But the most important aspect is that the processes of thermal conversion and hydrocracking are going without expensive catalysts.

[0029] The concept of “thermal conversion” or hydrocracking, as used in this invention, has the traditional meaning and includes bringing the cracked raw stock into contact with hydrogen—500-2,000 unit volumes of hydrogen or a hydrogen-containing gas at the standard conditions (T =0° C., P=0.1013 MPa) per one unit volume of the liquid raw stock at the pressure 4.0-15.0 MPa, the volumetric rate 1-3/hbur (conditional time of contact is 20-90 minutes) and the temperatures of 390-440° C.

[0030] In the course of the experimental verification of the technology furnaces with finned tubes and a hollow non-heated reactor were used. The data obtained in the laboratory conditions, both in the pressure vessel and in the continuous-flow unit having the reactor volume of 600 L, may be rather well simulated for conducting the process on the industrial scale in the plant with the capacity up to 420 m³ of raw stock.

[0031] The optimal conditions (temperature, pressure, volumetric rate) are those, at which the maximum quantity of the fmal product is obtained and no undesirable significant coke formation is observed, especially in the tube furnace and in the reactor. After the retention for a given period in the reactor unit the products of cracking are cooled down and separated, while extracting the desired products. The usual separation methods are evaporation at a reduced (in comparison to the reaction conditions) pressure, separation of the liquid products from the slime (concentrate of the solid products), which may be carried out by any known methods, e.g., centrifugation, filtration, etc, separation of the liquid and the vaporous products of the reaction, etc. We used the method of centrifuging with the application of a decanter centrifuge.

[0032] It should be noted that at thermal conversion or hydrocracking under the optimal conditions coke products in the amount up to 5% by weight are formed, which are not deposited on the walls of the reaction equipment, but are removed from the reactor together with the hydrogenate.

[0033] The known concepts on the mechanism, under which the organic mass of the solid activating additive is destructed, form the basis for the process. In the optimal conditions the processes of decomposition and liquefaction of the additive organic mass go with the formation of radicals, which have different molecular weights, and liquid products, which composition includes compounds having hydrogen-donor properties, that are tetrahydrate derivatives of condensed aromatic hydrocarbons, nitrogenous and oxygen-containing derivatives.

[0034] These chemically active compounds, which are formed from the organic mass of a solid additive in the conditions of the hydrocracking process, stipulate the destruction of high-boiling hydrocarbons, as included in the compositions of heavy still bottoms (fuel oil, tar oil), according to the chain-radical mechanism and contribute to the development of the hydrogenation reaction of raw stock compounds and products of their decomposition.

[0035] The liquid additive also possesses hydrogen-donor properties. A certain catalytic impact on the transformation of the initial raw stock and the products of its decomposition is exerted by the mineral part of the additive, which consists, to a significant degree, of aluminosilicates and ferric salts.

[0036] At hydrocracking of, e.g., tar oil in the presence of a solid activating additive, along with the deep destruction of the tar oil high-molecular hydrocarbons, the desulfurization of the raw stock, the destruction of the asphaltenes it contains, the deposition of the forming coke products as well as vanadium and nickel on the mineral part of the solid activating additive are also taken place.

[0037] A slate coal, which contains the mineral part (45-60% by weight) and the organic part (40-55% by weight), is used as the sapropelite. In particular, slate coals, which contain (in grams per ton) molybdenum 3-15, nickel 20-53, cobalt 3-10, chrome 30-40, copper 15-40 and lead 5-20, are used.

[0038] Furthermore, the mineral part of slate coals contains, in per cent by weight: SiO₂  30-40 Cao  25-40 Na₂O 0.3-3.0 Fe₂O₃   5-10 MgO 1.5-5.0 P₂O₅ 0.1-0.7 Al₂O₃   8-15 SO₃ 1.5-5.0 TiO₂ 0.5-0.7 K₂O 2.0-5.0

[0039] When the share of the mineral part is lower than 45% by weight, the reactions of cracking of raw stock (e.g., tar oil) go to a far lesser extent, which results in reducing the yield of the desired products (gasoline, diesel and gas-oil fractions) and increasing the quantity of the raw stock non-transformed in one pass.

[0040] When the share of the mineral part exceeds the limit of 60%, the cracking reactions for produced desired products develop with greater formation of undesired gaseous and coke-like products. Due to this, the yield of the desired fuel distillates is also reduced. The service life of the equipment is also reduced due to the erosion effect of the mineral part of the slate coal on the walls of the reaction apparatus (the furnace for heating the raw stock, the reactor, the heat-exchangers).

[0041] Any raw stock of this type—vacuum gas-oil, fuel oil, tar oil, heavy oils, natural bitumens.

[0042] As the liquid activating additive the shale oil is used, which consists of the fraction with the boil-off limits of 200 to 400° C. and containing hydrogen in the amount of at least 10.0% by weight. Such shale oil is produced by the known method, i.e., the heat treatment of slate coals with a solid heat carrier. According to the known method, the fine-grained slate coal is dried and subjected to thermal destruction with a solid heat carrier with the formation of a gas-vapor mixture. The latter, after its dry cleaning, is sprayed with a condensate mixture, and the first condensate of the heavy fraction of oil is removed. After this the gas-vapor mixture is cooled down in a condenser, and the second condensate of the heavy fraction of oil is removed as the finished product. The non-condensed part of the gas-vapor mixture is separated in a cracking fractionator, and the light fraction of oil is separated and removed as the finished product. This method enables to get from the slate coal its valuable fractions with a low content of mechanical impurities and to optimize the process parameters (see “The Chemistry and Technology of Shale Oil”, Ed. by N. I. Zelenin, “Khiniya” Publishers, Leningrad, 1986, p. 146).

[0043] A specific feature of the thus obtained shale oil fraction with the boiling point from 200 to 400° C. is that its composition includes elevated quantities of hydrogen (at least 10% by weight) due to the presence of a significant quantity of hydroderivative polycyclic aromatic compounds. These compounds are represented by a group of 2-4-ring hydroaromatics (di-, tetra- and hexaderivatives of alkyl naphthalene, anthracene, phenanthrene, benzanthracene, pyren, fluoranthen, chrysene). This fraction with the boiling point from 200 to 400° C. is a rather efficient donor of hydrogene at thermal conversion and hydrocracking of residual oil stock (preferably, tar oil). For obtaining the necessary quantities of the desired products by thermal conversion or hydrocracking the optimal content of hydrogen in shale oil with the boiling point from 200 to 400° C. should be at least 10% by weight. If the hydrogen quantity in shale oil is lowered to a value below 10% by weight, the yield of fuel distillates in the processes of thermal conversion and hydrocracking is significantly reduced. An increase of the hydrogen quantity in shale oil to a value above 12% by weight does not influence the yield of fuel distillates, but makes the final product more expensive. The shale oil fraction with the boil-off limits of 200 to 400° C. and containing hydrogen in the quantity of at least 10% by weight is introduced in the quantity of 1.0 to 6.0% by weight of the oil stock.

[0044] The use of hydrogen as the liquid donor enables to greatly reduce the consumption of hydrogen from the gaseous phase by the hydrocracking process. It has been established by the authors on the basis of the data obtained during the industrial tests that the consumption of hydrogen for the reactions was 0.7-0.9% by weight of the raw stock. In the process of thermal conversion hydrogen is consumed only from a slate coal and from the liquid donor of hydrogen. The lowering of the hydrogen consumption, in comparison to the known methods, has a positive impact on the technical and economic parameters of the inventive method and, in particular, contributes to cheapening of the final product.

[0045] A certain positive result may be also achieved when carrying out the processes of thermal conversion or hydrocracking in the presence either of a slate coal only or shale oil only. However, in both cases the yield of light oil products would be significantly lower due to the fact that the reaction system would not have the necessary quantity of hydroaromatics possessing the hydrogen-donor properties.

[0046] In order to achieve the desired yield of light oil products, it is necessary to increase the quantity of slate coal up to 10-12% of the raw stock, or to use the cleaned slate coal of “Kerogen-70” or “Kerogen-90” type (4-6% by weight of the raw stock). The quantity of shale oil with the boil-off limits of 200 to 400° C. should be increased up to 3.5-6% by weight of the raw stock. Any increase in the quantities of slate coal or shale oil results in a higher cost of the process.

[0047] The desired fuel distillates, when separating the products of thermal conversion and hydrocracking in accordance with the invention, are common broad fuel fractions: the gasoline fraction boiling off within the limits of 40-180° C., the diesel fuel fraction boiling off within the limits of 180-360° C., and the gas-oil fraction boiling off within the limits of 360-500° C.; their properties and methods of use are well known to specialists in the field of oil refining.

[0048] The produced fuel distillates may be re-refmed into the components of commercial fuels or to commercial fuels by the usual methods of oil refining that are common in the industry. For example, the gasoline fraction may be subjected to hydrorefining on special catalysts for the production oof the gasoline component having the octane number 82-93 under study method. The diesel fuel fraction after hydrorefining may be used as a commercial diesel fuel with the cetane number 48-50.

[0049] Such fuel fractions are the main products when carrying out the process in accordance with the invention. They may be easily re-refined into commercial fuels, i.e., this invention enables to get the result that is not obvious from the state of the art.

[0050] The installation scheme of the plant for implementing the inventive method is shown on the appended drawing. Lump (as-received) slate coal having the size of 25-250 mm or slate coal fmes having the size of 0-25 mm from railway cars arrives to the storage yard. Fro there the slate coal is supplied to the slate coal receiving hopper 1. The slate coal may be delivered from the storage yard to the receiving hopper 1 by trucks or on a band conveyor.

[0051] From the receiving hopper the slate coal is fed on the band conveyor to the crusher with the bag filter 2, where it is crushed to the particle size of 8 mm. The 8 mm slate coal particles is delivered to the “Desi-14” crusher 3, where the slate coal is further crushed for obtaining particles having the size of 1 mm. After the “Desi-14” crusher the crushed slate coal if fed via the discharging passage for the fmal grinding to the “Desi-14” disintegrator 4, where it is ground to the particle size less than 100 microns. The “Desi-14” disintegrator is equipped with a cyclone, an air filter, a bag filter and a star feeder.

[0052] From the “Desi-14” disintegrator the ground slate coal is fed via the discharging passage of the “Desi-14” disintegrator to the jigger screen with the mesh up to 140 microns, and then to the temporary storage bin 5. The complex for slate coal disintegration has the control panel with the protection and starting devices. The jigger screen is designed for separating slate coal particles having the size more than 140 microns.

[0053] Then the slate coal ground to the particle size of 100 microns is fed to the section for raw stock preparation. This stage is very important for the whole chain of the production process. The preparation of the raw stock is carried out as follows. To the heated mixer or another mixing device 9, at which the temperatures of 80-100° C. is maintained, the shale oil from the tank 7, the tar oil (or fuel oil) from the tank 8 and, last, the slate coal are fed by turns. First, to the mixing device 9 the shale oil is fed by the pump, then the tar oil from the tank 8 and the slate coal through the metering device 6 are fed. The operations of feeding the three components of the raw stock mixture are carried out while operating the mixing device for the purpose of preventing sedimentation of slate coal to the bottom of the mixer. If the mixing device may not ensure the efficient mixing of the 3-component mixture, it is advisable to use the pump-dispensers 10 for more thorough mixing (homogenization). At this time the temperature in the section for raw stock preparation should be maintained at the level of 80-100° C. for ensuring the tar oil pumpability.

[0054] After the mixer 9 the prepared raw stock mixture is delivered to the back-up mixer 11, from where it is fed by the raw stock high-pressure pump 12 to the heat exchanger 13 and from there—to the raw stock heating furnace 14. The furnace 14 has two sections—A and B. The temperature in the section A is maintained within the limits of 380-400° C., the temperature at the exit of the furnace is maintained at 460-490° C. depending on the type of treated raw stock. From the furnace the partially transformed raw stock is delivered to the lower part of the hollow non-heated reactor 15, where the reactions of the raw stock hydrocracking go at the hydrogen pressure 6-10 MPa, the volumetric rate of 1.0-2.0/hour and the reactor-height temperatures of 425-450° C. The hydrogen-containing gas (hydrogen content 80%) is fed in the quantity of 1,000-1,500 cubic meters per 1 cubic meter of the raw stock. After the reactor the gas-vapor flow is directed to the heat exchanger 13 and further to the hot separator 16, where the temperatures of 270-320° C. and the pressure 10 MPa are maintained. In these conditions, the fractions boiling off up to the temperatures of 360-380° C. mainly escape at the top part of the hot separator, and the fractions boiling off at the temperatures above 360-380° C. together with the solid products escape at the lower part of the hot separator. The upper flow in the hot separator together with the hydrogen-containing gas after passing through the cooling system 17 is accumulated in the high-pressure separator 18 where the hydrogen-containing gas is separated from the hydrogenate. The hydrogen-containing gas is fed for mixing with fresh hydrogen and then to the recirculation compressor 25.

[0055] The hydrogenate from the high-pressure separator passes to the low-pressure separator 19 and further via the pipeline to the accumulating tank for further refining. The product from the lower part of the hot separator (the so-called “slime”) goes via the baffle valve 20 to the cooler 21 for cooling and is transported via the pipeline to the decanter centrifuge 22 for separating the liquid products from the solid ones. The liquid products (the so-called “ftigat”) are mixed with the hydrogenate (the top part of the hot separator), and the mixture is fed, after heating in the furnace 24 to the cracking fractionator 26 for distillation in order to produce the gasoline fraction with the boilin g point up to 180° C., the diesel fuel fraction with the boiling point 180-360° C., the gas-oil fraction with the boiling point 360-500° C. and the residue (recycle) boiling off at temperatures above 500° C.

[0056] The solid products (slime) are collected in the receiver 23 and then are supplied to the bitumen production facilities for producing bitumens used in the road construction or are used as the raw stock for extracting vanadium, nickel and rare-earth metals from them.

[0057] It is necessary to note that another variant of the production flow chart—without the hot separator—is also possible. In this case the gaseous flow after the reactor passes the heat exchanger 13, the cooler 17, the high-pressure separator 18, the low-pressure separator 19 and the decanter centrifuge 22.

EXAMPLES OF THE POSSIBLE EMBODIMENTS

[0058] The advantages of the invention are illustrated with the following examples.

[0059] As the residual charge stock in the cited examples the tar oil from the mixture of Western Siberian oils is used, which has the following characteristics: density—984 kg/m³, elemental composition, in % by weight: C—86.8; H—10.86; S—1.5; N—0.3 (oxygen and impurities—the rest to 100.0), viscosity—28.0 sSt, coking ability—10.0% by weight, asphaltenes—9.3% by weight, boil off at temperatures lower 500° C.—24.5% by weight, contains vanadium—140 g/t, nickel—70 g/t.

[0060] As the sapropelite the as-received Baltic slate coal is used, which has the following characteristics, in % by weight: A^(d)—46.70; CO^(d) _(2 min)—8.32; C^(daf)—81.3; H^(daf)—9.25; N^(daf)—0.28; S^(d) _(t)—0.90; W^(d)—3.0.

[0061] As the liquid activating additive the shale oil is used, which consists of the fraction with the boil-off limits of 200-400° C. and has the following characteristics: density—995 kg/m³, refraction index—1.5696, molecular weight—290, asphaltenes content—3.8% by weight, elemental composition, in % by weight: C—82.95, H—10.0, S—0.6; pour point—minus 20° C., viscosity—14.9 sSt at 50° C.

[0062] The process of thermal conversion or hydrocracking of tar oil is carried out either in a continuous-flow plant with a 6 L reactor or in an industrial plant with a 10 m³ reactor. The conditions of thermal conversion are: temperature 425-450° C., pressure (of nitrogen, intrinsic hydrocarbon gases, hydrogen-containing gas) 3-5 MPa, volumetric rate 1.0-2.0/hour, gas recirculation 600-800 L per 1 L of the raw stock. The conditions of hydrocracking are: temperature 425-450° C., pressure (of hydrogen or hydrogen-containing gas) 6.0-10.0 MPa, volumetric rate 1.0-2.0/hour, gas recirculation 1,000-1,500 L per 1 L of the raw stock.

[0063] The quantity of the liquid aromatic additive is 0.5-6.0%, the quantity of sapropelite is 0.5-5.0% of the tar oil weight.

[0064] In the course of the process the gas and the liquid products are taken off, the solid components are separated. The liquid products of the process are distilled into the fractions with the boiling point up to 180° C., 180-360° C., 360-500° C. and the residue with the boiling point above 500° C.

[0065] The slate coal and oil mixture for the processes of thermal conversion or hydrocracking is prepared by successively mixing the residual charge stock, in particular tar oil, the fraction of shale oil with the boiling point 200-400° C. and as-received slate coal. The mixing is carried out in a heated mixer at the temperature not lower than 85° C. for 2.5 hours, and then the prepared mixture is subjected to homogenization in a disperser device or in a process activation plant.

[0066] Mixtures are thus produced, which do not break down for a long time.

Example 1

[0067] The base mixture was prepared by mixing 10 t of tar oil, 0.2 t of slate coal (mineral part content =40% by weight) and 0.3 t of the shale oil fraction with the boiling point 200 to 400° C. The mixing was carried out in a heated mixer at a temperature not lower than 85° C. for 2.5 hours. Then the mixture was subjected to activation and homogenization. Thermal conversion was carried out at the pressure 3-5 MPa, temperature 425-450° C., volumetric rate 1-2/hour. The resulting liquid products were subjected to centrifuging for separating the solid components. The liquid products were distilled into fractions having the boiling point up to 180° C. (gasoline), 180-360° C. (diesel fuel), 360-500° C. (gas-oil) and the residue with the boiling point above 500° C. The parameters of the process are given in Table 1.

Example 2

[0068] The raw stock and the thermal conversion process conditions were similar to those in Example 1, with the exception that the mineral part content of the slate coal was 45% by weight. The parameters of the thermal conversion process are given in Table 1.

Example 3

[0069] The raw stock and the thermal conversion process conditions were similar to those in Example 1, with the exception that the mineral part content of the slate coal was 50% by weight. The parameters of the thermal conversion process are given in Table 1.

Example 4

[0070] The raw stock and the thermal conversion process conditions were similar to those in Example 1, with the exception that the mineral part content of the slate coal was 60% by weight. The parameters of the thermal conversion process are given in Table 1.

Example 5

[0071] The raw stock and the thermal conversion process conditions were similar to those in Example 1, with the exception that the mineral part content of the slate coal was 65% by weight. The parameters of the thermal conversion process are given in Table 1.

Example 6

[0072] The base mixture was prepared by mixing 10 t of tar oil, 0.2 t of slate coal and 0.3 t of the shale oil fraction with the boiling point 200 to 400° C. and the hydrogen content of 10% by weight. The mixing was carried out in a heated mixer at a temperature not lower than 85 ° C. for 2.5 hours. Then the mixture was subjected to activation and homogenization. In this example the slate coal content was 0.5% by weight.

[0073] Thermal conversion was carried out at the pressure 3-4 MPa, temperature 430-450 ° C., volumetric rate 1-2/hour. The resulting liquid products were subjected to centrifuging for separating the solid components. The liquid products are distilled into fractions having the boiling point up to 180 ° C. (gasoline), 180-360 ° C. (diesel fuel), 360-500 ° C. (gas-oil) and the residue with the boiling point above 500° C. The parameters of the process are given in Table 2.

[0074] The resulting products had the following characteristics: the gasoline fraction with the boiling point up to 180 ° C.: refraction index 1.4216; elemental composition, in % by weight: C 84.53, H 13.75, S 0.46, N 0.06; the diesel fuel fraction with the boiling point 180-360 ° C.: refraction index 1.4786, elemental composition, in % by weight: C 85.89, H 12.26, S 0.69, N 0.06; the gas-oil fraction with the boiling point 360-500 ° C.: refraction index 1.521 1: elemental composition, in % by weight: C 86.60, H 11.24, S 1.29, N 0.21; the residue with the boiling point above 500 ° C.: density 1,011 kg/m³, elemental composition, in % by weight: C 88.18, H 9.48, S 1.70, N 0.64.

Example 7

[0075] The raw stock and the thermal conversion process conditions were similar to those in Example 6, except for the addition of the slate coal in the quantity of 1.0% by weight. The parameters of the thermal conversion process are given in Table 2.

[0076] Example 8

[0077] The raw stock and the thermal conversion process conditions were similar to those in Example 6, except for the addition of the slate coal in the quantity of 2.0% by weight. The parameters of the thermal conversion process are given in Table 2.

Example 9

[0078] The raw stock and the thermal conversion process conditions were similar to those in Example 6, except for the addition of the slate coal in the quantity of 3.0% by weight. The parameters of the thermal conversion process are given in Table 2.

Example 10

[0079] The raw stock and the thermal conversion process conditions were similar to those in Example 6, except for the addition of the slate coal in the quantity of 5.0% by weight. The parameters of the thermal conversion process are given in Table 2.

Example 11

[0080] The raw stock and the thermal conversion process conditions were similar to those in Example 6, with the exception that the quantity of the shale oil fraction with the boiling point 200-400 ° C. was 0.5% by weight. The parameters of the thermal conversion process are given in Table 2.

Example 12

[0081] The raw stock and the thermal conversion process conditions were similar to those in Example 6, with the exception that the quantity of the shale oil fraction with the boiling point 200-400° C. was 1.0% by weight. The parameters of the thermal conversion process are given in Table 2.

Example 13

[0082] The raw stock and the thermal conversion process conditions were similar to those in Example 6, with the exception of the quantity of the shale oil fraction with the boiling point 200-400° C. was 2.0% by weight. The parameters of the thermal conversion process are given in Table 2.

Example 14

[0083] The raw stock and the thermal conversion process conditions were similar to those in Example 6, with the exception that the quantity of the shale oil fraction with the boiling point 200-400° C. was 3.0% by weight. The parameters of the thermal conversion process are given in Table 2.

Example 15

[0084] The raw stock and the thermal conversion process conditions were similar to those in Example 6, with the exception that the quantity of the shale oil fraction with the boiling point 200-400° C. was 6.0% by weight. The parameters of the thermal conversion process are given in Table 2.

Example 16

[0085] The raw stock and the thermal conversion process conditions were similar to those in Example 6, with the exception that the quantity of the slate coal was 2.0% by weight. The parameters of the thermal conversion process are given in Table 2.

Example 17

[0086] The raw stock and the thermal conversion process conditions were similar to those in Example 6, with the exception that the quantity of the shale oil fraction with the boiling point 200-400° C. was 3.0% by weight. The parameters of the thermal conversion process are given in Table 2.

Example 18

[0087] The base mixture was prepared by mixing 7.5 t of tar oil, 2.5 t of recycle with the boiling point above 500° C., 0.2 t of slate coal and 0.3 t of the shale oil. The mixing was carried out in a heated mixer at a temperature not lower than 85° C. for 2.5 hours. Then the mixture was subjected to activation and homogenization. In this example the mineral part content of the slate coal was 40% by weight.

[0088] Hydrocracking of the tar oil mixed with the slate coal and the shale oil was carried out at the pressure 6-10 MPa, temperature 425-450° C., volumetric rate 1-2/hour, and the ratio of the hydrogen-containing gas to the tar oil was 1,000-1,500 Sm³ of the gas to 1 m³ of the raw stock.

[0089] The resulting liquid products were subjected to centrifuging for separating the solid components. The hydrogenate was distilled into fractions having the boiling point up to 180° C. (gasoline), 180-360° C. (diesel fuel), 360-500° C. (gas-oil) and the residue with the boiling point above 500° C. The residue with the boiling point above 500° C. was returned as the recycle for hydrocracking, being mixed with the base tar oil.

[0090] The resulting products had the following characteristics: the fraction with the boiling point up to 180° C.: refraction index 1.4728; elemental composition, in % by weight: C 86.25, H 12.20, S 1.26, N 0.07; the fraction with the boiling point 180-360° C.: refraction index 1.728, elemental composition, in % by weight: C 86.25, H 12.20, S 1.26, N 0.07; the fraction with the boiling point 360-500° C.: refraction index 1.5305: elemental composition, in % by weight: C 85.95, H 11.13, S 1.86, N 0.31; the residue with the boiling point above 500° C.: density 1,000 kg/m³, coking ability 6.5%, asphaltenes content 6.3%, vanadium content 300 g/t, nickel content 130 g/t; elemental composition, in % by weight: C 88.08, H 9.50, S 1.70, N 0.62.

Example 19

[0091] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the mineral part content of the slate coal was 45% by weight. The parameters of the hydrocracking process are given in Table 3.

Example 20

[0092] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the mineral part content of the slate coal was 50% by weight. The parameters of the hydrocracking process are given in Table 3.

Example 21

[0093] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the mineral part content of the slate coal was 60% by weight. The parameters of the hydrocracking process are given in Table 3.

Example 22

[0094] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the mineral part content of the slate coal was 65% by weight. The parameters of the hydrocracking process are given in Table 3.

Example 23

[0095] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the slate coal content was 0.5% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 24

[0096] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the slate coal content was 1.0% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 25

[0097] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the slate coal content was 2.0% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 26

[0098] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the slate coal content was 3.0% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 27

[0099] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the slate coal content was 5.0% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 28

[0100] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the quantity of the shale oil fraction with the boiling point 200-400° C. was 0.5% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 29

[0101] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the quantity of the shale oil fraction with the boiling point 200-400° C. was 1.0% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 30

[0102] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the quantity of the shale oil fraction with the boiling point 200-400° C. was 2.0% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 31

[0103] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the quantity of the shale oil fraction with the boiling point 200-400° C. was 3.0% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 32

[0104] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the quantity of the shale oil fraction with the boiling point 200-400° C. was 6.0% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 33

[0105] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the quantity of the slate coal was 2.0% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 34

[0106] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the quantity of the shale oil fraction with the boiling point 200-400° C. was 3.0% by weight. The parameters of the hydrocracking process are given in Table 4.

Example 35

[0107] The raw stock and the thermal conversion process conditions were similar to those in Example 6, with the exception that the hydrogen content of the shale oil fraction with the boiling point 200-400° C. was 8.0% by weight. The parameters of the thermal conversion process are given in Table 5.

Example 36

[0108] The raw stock and the thermal conversion process conditions were similar to those in Example 6, with the exception that the hydrogen content of the shale oil fraction with the boiling point 200-400° C. was 10% by weight. The parameters of the thermal conversion process are given in Table 5.

Example 37

[0109] The raw stock and the thermal conversion process conditions were similar to those in Example 6, with the exception that the hydrogen content of the shale oil fraction with the boiling point 200-400° C. was 12% by weight. The parameters of the thermal conversion process are given in Table 5.

Example 38

[0110] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the hydrogen content of the shale oil fraction with the boiling point 200-400° C. was 8.0% by weight. The parameters of the hydrocracking process are given in Table 5.

Example 39

[0111] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the hydrogen content of the shale oil fraction with the boiling point 200-400° C. was 8.0% by weight. The parameters of the hydrocracking process are given in Table 5.

Example 40

[0112] The raw stock and the hydrocracking process conditions were similar to those in Example 18, with the exception that the hydrogen content of the shale oil fraction with the boiling point 200-400° C. was 12.0% by weight. The parameters of the hydrocracking process are given in Table 5.

Example 41

[0113] In accordance with the method being the closest analogous solution according to RU Patent 2128207, the prepared mixture contained, in % by weight: tar oil -100.0, Baltic slate coal—2.0, including the mineral part—1.3; shale oil—3.0. The thermal cracking was carried out in then following conditions: temperature—425° C., pressure—4 MPa, volumetric rate—1.0/hour. The following yield was achieved, counting on tar oil, in % by weight: gas—7.8, water—1.0, the fraction with the boiling point 180-360° C.—42.9, the fraction with the boiling point 360-520° C.—15.1, the residue with the boiling point above 520° C.—22.5, coke on the mineral part of sapropelite—3.7.

Example 42

[0114] In accordance with the method being the closest analogous solution according to RU Patent 2128207, the prepared mixture contained, in % by weight: tar oil—100.0, Baltic slate coal—2.0, including the mineral part—1.3; shale oil—3.0; hydrogen consumption—2.5. The thermal cracking was carried out in then following conditions: temperature—425° C., pressure—10 MPa, volumetric rate—1.0/hour. The following yield was achieved, counting on tar oil, in % by weight: gas—6.0, water—0.5, the fraction with the boiling point up to 180° C.—19.0; the fraction with the boiling point 180-360° C.—63.0, the fraction with the boiling point 360-520° C.—11.0, the residue with the boiling point above 520° C.—1.5, coke on the mineral part of sapropelite—6.5. TABLE 1 Examples of the thermal conversion process depending on the quantity of the slate coal mineral part The raw stock contained, Examples No. in % by weight 1 2 3 4 5 1. Tar oil 100.0 100.0 100.0 100.0 100.0 2. Slate coal, 2.0 2.0 2.0 2.0 2.0 including the mineral part 40 45 50 60 65 3. The shale oil fraction with the 3.0 3.0 3.0 3.0 3.0 boiling point 200-400° C. 4. The process conditions: Temperature, ° C. 445 445 445 445 445 Pressure, MPa 4.0 4.0 4.0 4.0 4.0 Volumetric rate, hour⁻¹ 2.0 2.0 2.0 2.0 2.0 5. The product yield, counting on tar oil, in % by weight: Gas 4.0 4.9 5.0 7.0 10.5 Water 0.5 0.8 1.0 1.0 1.0 Fraction with the boiling point up to 180° C. 5.3 7.6 8.5 12.7 8.3 Fraction with the boiling point 180-360° C. 30.0 46.8 47.4 51.0 35.3 Fraction with the boiling point 360-500° C. 7.6 6.7 5.5 7.0 7.5 Fraction with the boiling point above 500° C. 56.0 36.4 35.6 23.2 35.9 Coke on the mineral part of slate coal 1.6 1.8 2.0 3.1 6.5

[0115] TABLE 2 Examples of the thermal conversion process The raw stock contained, Examples No. in % by weight 6 7 8 9 10 11 12 13 14 15 16 17 1. Tar oil 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 2. Slate coal, 0.5 1.0 2.0 3.0 5.0 2.0 2.0 2.0 2.0 2.0 2.0 — including the mineral part 0.3 0.6 1.2 1.8 3.0 1.2 1.2 1.2 1.2 1.2 1.2 — 3. The shale oil fraction with the 3.0 3.0 3.0 3.0 3.0 0.5 1.0 2.0 3.0 6.0 — 3.0 boiling point 200-400° C. 4. The process conditions: Temperature, ° C. 445 445 445 445 445 445 445 445 445 445 445 445 Pressure, MPa 4.0 4.0 3.0 4.0 4.0 4.0 4.0 4.0 3.0 4.0 4.0 4.0 Volumetric rate, hour⁻¹ 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 5. The product yield, counting on tar oil, in % by weight: Gas 4.5 5.3 7.0 7.8 10.8 4.8 4.9 6.5 7.0 7.5 6.0 6.1 Water 0.9 1.0 1.0 1.0 1.0 0.8 0.9 1.0 1.0 1.0 1.0 1.0 Fraction with the boiling point up to 6.2 8.1 12.7 13.6 8.5 5.8 7.7 11.8 12.7 13.2 5.3 5.6 180° C. Fraction with the boiling point 180-360° C. 35.7 47.9 51.0 54.2 38.5 34.3 45.7 47.9 51.0 52.3 35.5 33.7 Fraction with the boiling point 360-500° C. 7.5 6.3 7.0 8.3 5.3 8.0 8.5 8.8 7.0 9.0 7.0 8.6 Fraction with the boiling point above 46.2 33.0 23.2 16.8 36.9 46.5 32.6 24.4 23.2 21.0 43.0 43.5 500° C. Coke on the mineral part of slate coal 2.5 2.4 3.1 4.3 7.0 2.3 2.7 3.6 3.1 4.0 4.2 4.5

[0116] TABLE 3 Examples of the hydrocracking process depending on the quantity of the slate coal mineral part The raw stock contained, Examples No. in % by weight 1 2 3 4 5 1. Tar oil 75 75 75 75 75 Recycle with the boiling point above 500° C. 25 25 25 25 25 2. Slate coal, 2.0 2.0 2.0 2.0 2.0 including the mineral part 40 45 50 60 65 3. The shale oil fraction with the boiling 3.0 3.0 3.0 3.0 3.0 point 200-400° C. 4. Hydrogen consumption 0.7 0.8 0.8 0.9 1.5 5. The process conditions: Temperature, ° C. 445 445 445 445 445 Pressure, MPa 4.0 4.0 4.0 4.0 4.0 Volumetric rate, hour⁻¹ 2.0 2.0 2.0 2.0 2.0 Ratio: hydrogen-containing gas/raw stock, Sm³/m³ 1,400 1,400 1,400 1,400 1,400 5. The product yield, counting on tar oil, in % by weight: Gas 6.2 6.0 6.3 6.8 11.6 Water 0.9 1.0 1.0 1.0 0.8 Fraction with the boiling point up to 180° C. 18.1 19.0 20.6 21.0 12.0 Fraction with the boiling point 180-360° C. 53.4 56.1 60.7 60.3 58.0 Fraction with the boiling point 360-500° C. 13.0 13.5 12.4 11.7 15.1 Fraction with the boiling point above 500° C. 9.0 5.5 1.6 1.7 2.5 Coke on the mineral part of slate coal 4.4 3.9 3.2 3.4 6.5

[0117] TABLE 4 Examples of the hydrocracking process The raw stock contained, Examples No. in % by weight 23 24 25 26 27 28 29 30 31 32 33 34 1. Tar oil 75 75 75 75 75 75 75 75 75 75 75 75 Recycle with the boiling 25 25 25 25 25 25 25 25 25 25 25 25 point above 500° C. 2. Slate coal, 0.5 1.0 2.0 3.0 5.0 2.0 2.0 2.0 2.0 2.0 2.0 — including the mineral part 0.3 0.6 1.2 1.8 3.0 1.2 1.2 1.2 1.2 1.2 1.2 — 3. The shale oil fraction with 3.0 3.0 3.0 3.0 3.0 0.5 1.0 2.0 3.0 6.0 — 3.0 the boiling point 200-400° C. 4. The process conditions: Temperature, ° C. 445 445 445 445 445 445 445 445 445 445 445 445 Pressure, MPa 10 10 10 10 10 10 10 10 10 10 10 10 Volumetric rate, hour⁻¹ 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 Ratio: hydrogen-containing 1,400 1,400 1,400 1,400 1,400 1,400 1,400 1,400 1,400 1,400 1,400 1,400 gas/raw stock, Sm³/m³ 5. The product yield, counting on tar oil, in % by weight: Gas 5.4 5.9 6.3 7.1 10.9 5.8 6.0 6.5 6.3 7.2 5.7 5.8 Water 0.8 1.0 1.0 1.0 0.9 1.0 0.9 1.0 1.0 1.0 1.1 0.9 Fraction with the boiling 17.8 17.8 20.6 21.3 11.3 8.9 10.0 18.3 20.6 21.4 8.0 10.0 point up to 180° C. Fraction with the boiling 53.4 54.9 60.7 59.7 59.0 47.7 48.5 57.1 60.7 60.9 42.6 40.0 point 180-360° C. Fraction with the boiling 11.1 11.8 12.4 12.7 18.2 17.5 18.0 16.9 12.4 13.4 13.0 7.7 point 360-500° C. Fraction with the boiling 10.5 8.8 1.7 1.6 3.0 18.2 16.4 1.7 1.7 1.5 27.1 32.7 point above 500° C. Coke on the mineral 4.5 3.8 3.2 3.5 5.9 4.2 4.0 3.4 3.2 3.6 4.5 5.9 part of slate coal

[0118] TABLE 5 Examples of the thermal conversion and hydrocracking processes depending on the hydrogen content of shale oil Examples At thermal The raw stock contained, conversion At hydrocracking No. in % by weight 35 36 37 38 39 40 41 42 1. Tar oil 100.0 100.0 100.0 75.0 75.0 75.0 100.0 60.0 Recycle with the boiling point above 500° C. — — — 25.0 25.0 25.0 — 40.0 2. Slate coal, 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 including the mineral part 1.2 1.2 1.2 1.2 1.2 1.2 1.3 1.3 3. The shale oil fraction with the boiling point 200-400° C., 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 including hydrogen content of it 8.0 10.0 12.0 8.0 10.0 12.0 8.5 8.5 4. Hydrogen consumption — — — 0.9 1.0 1.1 — 2.5 5. The process conditions: Temperature, ° C. 445 445 445 445 445 445 445 445 Pressure, MPa 4.0 4.0 4.0 10.0 10.0 10.0 4.0 10.0 Volumetric rate, hour⁻¹ 2.0 2.0 2.0 2.0 2.0 2.0 1.0 1.0 Ratio: hydrogen-containing gas/raw stock, Sm³/m³ — — — 1,400 1,400 1,400 — 1,000 5. The product yield, counting on tar oil, in % by weight: Gas 5.1 7.5 7.7 6.1 7.5 7.8 7.8 3.0 Water 0.9 1.0 1.0 0.9 1.0 1.0 1.0 0.5 Fraction with the boiling point up to 180° C. 10.2 11.5 12.2 16.3 23.1 23.6 12.0 19.0 Fraction with the boiling point 180-360° C. 45.0 49.1 50.8 43.4 62.8 63.2 42.9 63.0 Fraction with the boiling point 360-500° C. 6.1 16.9 17.8 13.5 6.3 5.5 15.1 11.0 Fraction with the boiling point above 500° C. 34.1 15.0 11.7 22.1 1.3 1.2 22.5 1.5 Coke on the mineral part of slate coal 3.6 4.0 3.9 3.6 4.0 3.8 3.7 6.5

[0119] The analysis of the data given in Table I shows the following. With the increase of the mineral part content of the slate coal from 40 to 50% by weight, at thermal conversion of tar oil the fuel distillates yield increases from 35.3 (in the conditions of Example 1) to 55.9% by weight (in the conditions of Example 3), and the increase of the mineral part content of the slate coal to 60% by weight (in the conditions of Example 4) results in increasing the fuel distillates yield to 63.7% by weight (in the conditions of Example 4). The further increase of the mineral part content of the slate coal to 65% by weight does not result in an increase in the fuel distillates yield, but, rather, to its lowering to 43.6% by weight (in the conditions of Example 5). The undesired reactions—formation of gaseous products in great quantities (10.5% by weight) and coke (6.5% by weight)—develop in the conditions of Example 5.

[0120] Thus, the comparison of the data on thermal conversion in Examples 2, 3 and 4 shows that the technical result of this invention is achieved due to the mineral part content of the slate coal, equal to 45-60% by weight, and due to the use, as the liquid activating additive, of the shale oil fraction with the boiling point 200-400° C. in the amount of 3.0% by weight of the raw stock. The slate coal mineral part content of 40 and 65% does not ensure the achievement of the technical result in the process of thermal conversion of tar oil.

[0121] The analysis of the data given in Table 2 shows the following. Examples 6-10 illustrate this invention, in which slate coal is used as the solid activating additive at thermal conversion of tar oil. The tar oil content in the said Examples is (in % by weight): 0.5, 1.0, 2.0, 3.0, 5.0. The total yield of the fractions with the boiling points up to 180° C., 180-360° C., and 360-500° C. is in its maximum at 70.7-76.1 (% by weight, counting on the tar oil, for Examples 8 and 9). At the slate coal content of 5% by weight the fuel distillates yield is lower than at that of 2.0 and 3.0% by weight counting on tar oil. If the slate coal content is less than 1.0% by weight, the technical result of the invention may not be achieved due to lowering in the yield of the desired product. Exceeding the 5% limit of the slate coal content does not result in an increase in the desired product yield, but only contributes to rise in the cost of the final product of the tar oil thermal conversion process. due to ineffective consumption of slate coal.

[0122] Thus, slate coal should be added to tar oil in the amounts of 1.0-5.0% by weight with respect of the raw stock. The quantity of the liquid activating additive should be 1.0-6.0% by weight, counting on the tar oil.

[0123] Examples 11-15 illustrate this invention in which the shale oil fraction with the boiling point 200-400° C. is used as the liquid activating additive. The content of the said additive in Examples 11-15 is (in % by weight), respectively, 0.5, 1.0, 2.0, 3.0, and 6.0 counting on tar oil. The total yield of the fractions with the boiling points up to 180 ° C., 180-360 ° C., and 360-500 ° C. is in its maximum at 68.5-70.7 (in the conditions of Examples 13 and 14). With the liquid additive content of 6.0% by weight the desired products yield is slightly higher (74.5% by weight in the conditions of Example 15). Exceeding the 6% content limit of the fraction with the boiling point 200-400 ° C. results only in a significant rise in the cost of the final product due to ineffective consumption of shale oil.

[0124] Thus, the shale oil fraction with the boiling point 200-400 ° C. with its hydrogen content not less than 10.0% by weight should be added to the residual oil stock in the amount of 1.0-6.0% by weight, counting on the raw stock.

[0125] Example 16 illustrates the use, while carrying out the tar oil thermal conversion process according to this invention, of slate coal only in the amount of 2.0% by weight, counting on tar oil. The yield of the three fractions (boiling points up to 180 ° C., 180-360 ° C., 360-500 ° C.) in the conditions of Example 16 is 57.8% by weight, counting on tar oil.

[0126] Example 17 illustrates the parameters of the tar oil thermal conversion process, in which the shale oil fraction with the boiling point 200-400 ° C. and hydrogen content of 10.0% by weight is used as the liquid activating additive. The desired products yield in the conditions of Example 17 is 47.9% by weight, counting on tar oil.

[0127] The analysis of the data given in Table 3 shows the following. With the increase of the mineral part content of the slate coal from 40 to 50% by weight, at hydrocracking of tar oil the fuel distillates yield increases from 84.5 (in the conditions of Example 18) to 93.7% by weight (in the conditions of Example 20), and the increase of the mineral part content of the slate coal to 60% by weight (in the conditions of Example 21) does not result in an increase in the desired products yield and is 93.0% by weight (in the conditions of Example 21). The further increase of the mineral part content of the slate coal to 65% by weight results in a lowering of the fuel distillates yield to 85.1% by weight (in the conditions of Example 22). In these conditions the undesired reactions—formation of gaseous hydrocarbons CIC₄, H₂S in great quantities (11.6% by weight) and coke products (6.5% by weight)—develop (Example 22).

[0128] Thus, the comparison of the data on hydrocracking in Examples 18, 20 and 21 shows that the technical result of this invention is achieved due to the use of the slate coal with its mineral part content equal to 45-60% by weight and due to the use, as the liquid activating additive, of the shale oil fraction with the boiling point 200-400 ° C., having the hydrogen content not less than 10.0% by weight, in the amount of 3.0% by weight of the raw stock. The slate coal mineral part content of 40 and 65% does not ensure the achievement of the technical result in the process of hydrocracking of tar oil.

[0129] The analysis of the results given in Table 4 shows the following. Examples 23-27 illustrate this invention, in which slate coal is used as the solid activating additive at hydrocracking of tar oil. The tar oil content in Examples 23-27 is (in % by weight): 0.5, 1.0, 2.0, 3.0, 5.0. The total yield of the fractions with the boiling points up to 180° C., 180-360° C., and 360-500° C. is in its maximum at 93.7% by weight, counting on tar, for Examples 25 and 26. At the slate coal content of 5% by weight the fuel distillates yield is lower than at that of 2.0 and 3.0% by weight counting on tar oil. If the slate coal content is less than 1.0% by weight, the technical result of the invention may not be achieved due to lowering in the yield of the desired products. Exceeding the 5% limit of the slate coal content does not result in an increase in the desired product yield, but only contributes to rise in the cost of the final product of the tar oil hydrocracking process due to ineffective consumption of slate coal.

[0130] Thus, slate coal should be added to tar oil in the amounts of 1.0-5.0% by weight with respect of the raw stock. The quantity of the liquid activating additive should be 1.0-6.0% by weight, counting on the tar oil.

[0131] Examples 28-32 illustrate this invention in which the shale oil fraction with the boiling point 200-400° C. and the hydrogen content not less than 10.0% by weight is used as the liquid activating additive at hydrocracking of tar oil. The content of the said additive in Examples 28-32 is, respectively, 0.5, 1.0, 2.0, 3.0, and 6.0 in % by weight, counting on the raw stock. The total yield of the fractions with the boiling points up to 180° C., 180-360° C., and 360-500° C. is in its maximum at 92.3-93.7 (in the conditions of Examples 30 and 31). With the liquid additive content of 6.0% by weight the desired products yield is slightly higher (95.7% by weight in the conditions of Example 32), but exceeding the 3% content limit of the shale oil fraction with the boiling point 200-400° C. results in rise in the cost of the desired products due to ineffective consumption of shale oil, while insignificantly increasing their yield.

[0132] Thus, the shale oil fraction with the boiling point 200-400° C. with its hydrogen content not less than 10.0% by weight should be added to the residual oil stock in the amount of 1.0-6.0% by weight, counting on the raw stock.

[0133] Example 33 illustrates the use, while carrying out the hydrocracking process according to this invention, of slate coal only in the amount of 2.0% by weight, counting on tar oil. The yield of the three fractions (boiling points up to 180° C., 180-360° C., 360-500° C.) in the conditions of Example 33 is 63.6% by weight, counting on tar oil.

[0134] Example 34 illustrates the parameters of the tar oil hydrocracking process, in which the shale oil fraction with the boiling point 200-400° C. is used, as the liquid activating additive, in the amount of 3.0% by weight, counting on the tar oil. The desired products yield in the conditions of Example 34 is 57.7% by weight, counting on the tar oil.

[0135] The analysis of the data given in Table 5 shows the following. Examples 35, 36, 37 illustrate this invention in respect of tar oil thermal conversion, in which the shale oil fraction with the boiling point 200-400° C. and with the hydrogen content of 8.0, 10.0 and 12% by weight is used as the liquid activating additive. The hydrogen content of the tar oil in Example 35 is 8.0% by weight, in Example 36-10% by weight, in Example 37-12% by weight. The total yield of the fractions with the boiling points up to 180° C., 180-360° C., and 360-500° C. is 77.5% by weight, counting on tar oil, in the conditions of Example 36.

[0136] Lowering the hydrogen content of the shale oil fraction to 8.0% by weight in the conditions of Example 35 results in lowering the desired fractions yield to 61.3% by weight, counting on the tar oil.

[0137] Raising the hydrogen content of the shale oil fraction to 12% by weight in the conditions of Example 37 does not result in a significant increase in the desired fractions yield (the desired fractions yield in the conditions of Example 37 is 80.8% by weight) and contributes only to rise in the cost of the final product due to ineffective consumption of shale oil. Thus, the quantity of the added shale oil with the boiling point 200-400° C. and the hydrogen content of 10-12% by weight should be 1.0-6.0% by weight.

[0138] Examples 38, 39, 40 illustrate this invention in respect of tar oil hydrocracking, in which the shale oil fraction with the boiling point 200-400° C. and with the hydrogen content of 8.0, 10.0 and 12% by weight is used as the liquid activating additive. The total yield of the fractions with the boiling points up to 180° C., 180-360° C., and 360-500° C. is 92.2% by weight, counting on tar oil, in the conditions of Example 39, while the hydrogen consumption from the gaseous phase was 1.0% by weight of the raw stock.

[0139] Lowering the hydrogen content of the shale oil fraction to 8.0% by weight in the conditions of Example 38 results in lowering the desired fractions yield to 73.2% by weight.

[0140] Raising the hydrogen content of the shale oil fraction to 12% by weight in the conditions of Example 40 does not result in a significant increase in the desired fractions yield (the desired fractions yield in the conditions of Example 40 is 92.3% by weight). Thus, the quantity of the added shale oil fraction with the boiling point 200-400° C. and the hydrogen content not less than 10% by weight should be 1.0-6.0% by weight.

[0141] It follows from the comparison of the results of the method under this invention, according to Examples 4, 8, 14, 21, 25, 31, 36, 39 and Examples 41 and 42, as characterize the closes analogous method (RU 2128207), in which the hydrogenated fraction with the boiling point 300-400° C. is used as the activating additive, that, owing to the use of slate coal with the mineral part content proposed in accordance with this invention, the shale oil fraction with the boiling point 200-400° C. and the hydrogen content not less than 10.0% by weight, and homogenization in the mixer, it is possible to eliminate the use of the expensive hydrogenated aromatic additive with the boiling point 300-400° C., while practically maintaining the product yield at the level of 90-93% by weight with respect to tar oil. The mechanical and chemical activation also results in a certain increase of the total yield of the product, as compared to the prototype, and, being combined with the above characteristic features of this invention enables to reduce the hydrogen consumption at hydrocracking of tar oil.

[0142] Thus, this invention ensures the achievement of the technical result that is not obvious from the state of the art.

INDUSTRIAL APPLICABILITY

[0143] This invention may be most successfully utilized in oil refining for producing fuel distillates, which are raw stock for the production of motor fuels and jet engine fuels. 

What is claimed is:
 1. The method for producing fuel distillates, including the mixing of residual oil stock with ground sapropelite and a liquid activating additive, homogenization and thermal conversion or hydrocracking of the resulting mixture with the subsequent extraction of the desired products, characterized in that said ground sapropelite is, prior to homogenization, mechanically and chemically activated in, at least, one disperser, a slate coal containing the mineral part in the amount of 45-60% by weight and the organic part in the amount of 40-55% by weight is used as said sapropelite, shale oil fraction with the boil-off limits of 200-400° C. and the hydrogen content not less than 10.0% by weight is used as the liquid activating additive, said slate coal and shale oil fraction being taken, counting on raw stock, in the quantity of 1.0-5.0% by weight and 1.0-6.0% by weight, respectively.
 2. The method according to claim 1, characterized in that slate coals are used that contain, grams per ton: molybdenum 3-15, nickel 20-35, cobalt 3-10, chrome 30-40, copper 15-40 and lead 5-20.
 3. The method according to claim 1, characterized in that slate coals are used, which mineral part contain, in % by weight: SiO₂  30-40 Cao  25-40 Na₂O 0.3-3.0 Fe₂O₃   5-10 MgO 1.5-5.0 P₂O₅ 0.1-0.7 Al₂O₃   8-15 SO₃ 1.5-5.0 TiO₂ 0.5-0.7 K₂O 2.0-5.0


4. The method according to claim 1, characterized in that homogenization is carried out in a mixer at a temperature from 80° C. to 100° C.
 5. The method according to claim 1, characterized in that said slate coal, being mechanically and chemically activated, is ground to the particle size of 30 to 100 microns. 